Identifying targets of potential concern by a screening level ecological risk assessment of human use pharmaceuticals in China.

The pollution of pharmaceuticals has attracted a lot of concerns during recent years. The goal of this study was to identify targets of ecological concern considering human use pharmaceuticals marketed in China. We constructed a database for 593 active pharmaceutical ingredients (APIs) by collecting their information on use and emission (e.g. production, human excretion, and removal by wastewater treatment) to calculated predicted environmental concentrations (PECs) by using an adapted European Medicines Agency method. PECs were comparable to the reported measurements for most APIs, demonstrating that the adapted method is reliable for the prioritization practice. Then PECs were compared to toxicity thresholds of three aquatic taxa (algae, daphnia, and fish). As a result, a total of 31 APIs, which were potentially risky and should be taken into consideration in future studies, were identified. Three APIs would pose a high risk with risk quotient (RQ) greater than 10. Six APIs were identified with moderate risks (1 < RQ < 10), and four of them were not reported before: rifaximin, griseofulvin, amikacin, and niclosamide. Of the 22 APIs with low risks (0.1 < RQ < 1), 17 have never been monitored previously in China and even worldwide. This study has yielded some probable antibiotics that should be considered as monitoring targets in China in the future.